# -*- coding: utf-8 -*-
def prime(n):
    lis = {}
    for i in range(2,n+1):
        if not i in lis:
            lis[i] = 1
            k = i*2
            while k <= n:
                lis[k] = 0
                k = k+i
    ans = []
    for i in lis:
        if lis[i] == 1:
            ans.append(i)
    return ans
def isprime(n):
    import math
    if n <= 1:
        return False
    for i in range(2, int(math.sqrt(n)) + 1):
        if n % i == 0:
            return False
    return True
def main():
    #print(len(prime(4000000)))
    if isprime(23423422):
        print('shi')
    else:print('no')
if __name__ == '__main__':
    import time
    start = time.time()
    main()
    print('Execution time: {0} seconds'.format(time.time() - start))
